It has heretofore been proposed to induce polymorphic transition of graphite to diamond by subjecting a starting material to high pressure shock compression. The U.S. Pat. Nos. 3,499,732, 3,653,792 and 3,659,972, to Garrett for example, propose the use of shaped electrically detonated explosive charges to obtain spherically symmetrical implosion shock waves for forming diamonds from graphite or for sintering powdered metals. One significant problem associated with this technique is one of physical size: the mass of explosive material involved would be on the order of thirty kilograms. An explosion of this size requires extraordinary containment precautions, and also raises problems in connection with recovery and contamination of the sample. Smaller explosive masses cannot be uniformly ignited using the electrical detonation techniques proposed in the art.
Another significant problem with the above proposed techniques is the lack of control of the implosive pressure afforded by shock compression techniques. Yet another problem with the electrically ignited explosive system is that of achieving a high degree of spherical symmetry in the detonating explosive.